Fig. 2 presents morphologies of normal mix (NM), modified
mixes (MM-10% and MM-20%) as well as latex-film. NM was observed
to entertain voids or inter particle spacing including gaps at interfacial boundary between cement oxides and aggregate particle
as portrayed on the lower right portion of Fig. 2a. Indeed, the
comparatively porous textured features shown in this matrix indicates
a typical level of porosity associated with normal mixes.
Modified mixes on the other hand, have shown more compacted
features depending upon the latex contents included in
the mix. For instance, while MM-10% shown in Fig. 2b yielded a
relatively denser texture than NM, MM-20% shown in Fig. 2c portrayed
a texture free from inter particle gaps. In fact, except for
shallow depressions, modification by 20% latex/water appeared
to have completely filled up voids and possibly coated all surfaces
of cement oxides as well as aggregates particles.
The latex-film in its entity has demonstrated a fine-grain textured
membrane as shown in Fig. 2d. In its liquid state, NRL mainly
consists of a dispersion of poly 1–4 isoprene particles. However, as
the dispersed medium which is normally water, drains away,
inter-particle spacing diminishes until coalesceness is achieved,
thereby resulting into a continuous film